linux/arch/c6x/kernel/head.S

82 lines
1.5 KiB
ArmAsm

; SPDX-License-Identifier: GPL-2.0-only
;
; Port on Texas Instruments TMS320C6x architecture
;
; Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
; Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
;
#include <linux/linkage.h>
#include <linux/of_fdt.h>
#include <asm/asm-offsets.h>
__HEAD
ENTRY(_c_int00)
;; Save magic and pointer
MV .S1 A4,A10
MV .S2 B4,B10
MVKL .S2 __bss_start,B5
MVKH .S2 __bss_start,B5
MVKL .S2 __bss_stop,B6
MVKH .S2 __bss_stop,B6
SUB .L2 B6,B5,B6 ; bss size
;; Set the stack pointer
MVKL .S2 current_ksp,B0
MVKH .S2 current_ksp,B0
LDW .D2T2 *B0,B15
;; clear bss
SHR .S2 B6,3,B0 ; number of dwords to clear
ZERO .L2 B13
ZERO .L2 B12
bss_loop:
BDEC .S2 bss_loop,B0
NOP 3
CMPLT .L2 B0,0,B1
[!B1] STDW .D2T2 B13:B12,*B5++[1]
NOP 4
AND .D2 ~7,B15,B15
;; Clear GIE and PGIE
MVC .S2 CSR,B2
CLR .S2 B2,0,1,B2
MVC .S2 B2,CSR
MVC .S2 TSR,B2
CLR .S2 B2,0,1,B2
MVC .S2 B2,TSR
MVC .S2 ITSR,B2
CLR .S2 B2,0,1,B2
MVC .S2 B2,ITSR
MVC .S2 NTSR,B2
CLR .S2 B2,0,1,B2
MVC .S2 B2,NTSR
;; pass DTB pointer to machine_init (or zero if none)
MVKL .S1 OF_DT_HEADER,A0
MVKH .S1 OF_DT_HEADER,A0
CMPEQ .L1 A10,A0,A0
[A0] MV .S1X B10,A4
[!A0] MVK .S1 0,A4
#ifdef CONFIG_C6X_BIG_KERNEL
MVKL .S1 machine_init,A0
MVKH .S1 machine_init,A0
B .S2X A0
ADDKPC .S2 0f,B3,4
0:
#else
CALLP .S2 machine_init,B3
#endif
;; Jump to Linux init
#ifdef CONFIG_C6X_BIG_KERNEL
MVKL .S1 start_kernel,A0
MVKH .S1 start_kernel,A0
B .S2X A0
#else
B .S2 start_kernel
#endif
NOP 5
L1: BNOP .S2 L1,5